<style>
  .demo-slide--vertical {
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(to bottom right, #5193e9, #0e61cd);
    color: #fff;
    font-size: 48px;
  }
  .container {
    --banana-carousel-vertical-height: 300px;
  }
</style>
<b-carousel class="container" vertical>
  <div class="demo-slide--vertical">1</div>
  <div class="demo-slide--vertical">2</div>
  <div class="demo-slide--vertical">3</div>
  <div class="demo-slide--vertical">4</div>
  <div class="demo-slide--vertical">5</div>
</b-carousel>
